Onur Güntürkün

Ruhr-Universität Bochum, Bochum, North Rhine-Westphalia, Germany

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Publications (280)1133.49 Total impact

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    ABSTRACT: Extinction learning provides the ability to flexibly adapt to new contingencies by learning to inhibit previously acquired associations in a context-dependent manner. The neural networks underlying extinction learning were mostly studied in rodents using fear extinction paradigms. To uncover invariant properties of the neural basis of extinction learning, we employ pigeons as a model system. Since the prefrontal cortex (PFC) of mammals is a key structure for extinction learning, we assessed the role of N-methyl-D-aspartate receptors (NMDARs) in the nidopallium caudolaterale (NCL), the avian functional equivalent of mammalian PFC. Since NMDARs in PFC have been shown to be relevant for extinction learning, we locally antagonized NMDARs through 2-Amino-5-phosphonovalerianacid (APV) during extinction learning in a within-subject sign-tracking ABA-renewal paradigm. APV-injection slowed down extinction learning and in addition also caused a disinhibition of responding to a continuously reinforced control stimulus. In subsequent retrieval sessions, spontaneous recovery was increased while ABA renewal was unaffected. The effect of APV resembles that observed in studies of fear extinction with rodents, suggesting common neural substrates of extinction under both appetitive and aversive conditions and highlighting the similarity of mammalian PFC and the avian caudal nidopallium despite 300 million years of independent evolution.
    Frontiers in Behavioral Neuroscience 04/2015; 9(85). DOI:10.3389/fnbeh.2015.00085 · 4.16 Impact Factor
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    ABSTRACT: Serotonin 1A receptors (5-HT1ARs), which are widely distributed in the mammalian brain, participate in cognitive and emotional functions. In birds, 5-HT1ARs are expressed in prosencephalic areas involved in visual and cognitive functions. Diverse evidence supports 5-HT1AR-mediated5-HT-induced ingestive and sleep behaviors in birds. Here, we describe the distribution of 5-HT1ARs in the hypothalamus and brainstem of birds, analyze their potential roles in sleep and ingestive behaviors, and attempt to determine the involvement of auto-/hetero-5-HT1ARs in these behaviors. In 6 pigeons, the anatomical distribution of [(3)H]8-OH-DPAT binding in the rostral brainstem and hypothalamus was examined. Ingestive/sleep behaviors were recorded (1h) in 16 pigeons pretreated with MM77 (a heterosynaptic 5-HT1AR antagonist; 23 or 69 nmol) for 20min, followed by intracerebroventricular ICV injection of 5-HT (N:8; 150 nmol), 8-OH-DPAT (DPAT, a 5-HT 1A,7R agonist, 30 nmol N:8) or vehicle. 5-HT- and DPAT-induced sleep and ingestive behaviors, brainstem 5-HT neuronal density and brain 5-HT content were examined in 12 pigeons, pretreated by ICV with the 5-HT neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) or vehicle (N:6/group). The distribution of brainstem and diencephalic c-Fos immunoreactivity after ICV injection of 5-HT, DPAT or vehicle (N:5/group) into birds provided with or denied access to water is also described. 5-HT1ARs are concentrated in the brainstem 5-HTergic areas and throughout the periventricular hypothalamus, preoptic nuclei and circumventricular organs. 5-HT and DPAT produced a complex c-Fos expression pattern in the 5-HT1AR-enriched preoptic hypothalamus and the circumventricular organs, which are related to drinking and sleep regulation, but modestly affected c-Fos expression in 5-HTergic neurons. The 5-HT-induced ingestivebehaviors and the 5-HT- and DPAT-induced sleep behaviors were reduced by MM77 pretreatment. 5,7-DHT increased sleep per se, decreased tryptophan hydroxylase expression in the raphe nuclei and decreased prosencephalic5-HT release but failed to affect 5-HT- or DPAT-induced drinking or sleep behavior. 5-HT- and DPAT-induced ingestive and sleep behaviors in pigeons appear to be mediated by heterosynaptic and/or non-somatodendritic presynaptic 5-HT1ARs localized to periventricular diencephalic circuits. Copyright © 2015. Published by Elsevier B.V.
    Behavioural brain research 04/2015; DOI:10.1016/j.bbr.2015.03.059 · 3.39 Impact Factor
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    ABSTRACT: Functional hemispheric asymmetry is a common feature of vertebrate brain organization, yet little is known about how hemispheric dominance is implemented at the neural level. One notable example of hemispheric dominance in birds is the leading role of the left hippocampal formation in controlling navigational processes that support homing in pigeons. Relying on resting state fMRI analyses (where Functional connectivity (FC) can be determined by placing a reference 'seed' for connectivity in one hemisphere), we show that following seeding in either an anterior or posterior region of the hippocampal formation of homing pigeons and starlings, the emergent functional connectivity maps are consistently larger following seeding of the left hippocampus. Left seedings are also more likely to result in functional connectivity maps that extend to the contralateral hippocampus and outside the boundaries of the hippocampus. The data support the hypothesis that broader functional connectivity is one neural-organizational property that confers, with respect to navigation, functional dominance to the left hippocampus of birds. This article is protected by copyright. All rights reserved. © 2015 Wiley Periodicals, Inc.
    Hippocampus 03/2015; DOI:10.1002/hipo.22462 · 4.30 Impact Factor
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    ABSTRACT: The corpus callosum (CC), the largest commissure in the human brain, is thought to play an essential part in the formation and maintenance of lateralized cognitive and motor functions. In particular, it has been suggested that inhibition of the subdominant hemisphere via commissural fiber tracts plays a crucial role for functional lateralization. However, many studies supporting this idea have either been conducted in nonhuman model species or used indirect measures of callosal functioning. In order to directly assess the impact of the presence or absence of the CC on both the existence and the extent of functional hemispheric asymmetries, we investigated handedness and language lateralization, as well as interhemispheric information integration, in 6 high-functioning individuals with partial or complete agenesis of the CC (AgCC). Performance was compared with that of 30 IQ- and age-matched controls with intact CC. We found a stronger predisposition for ambidexterity in individuals with AgCC. Similarly, the typical right ear advantage in the dichotic listening task was significantly reduced in AgCC. Furthermore, AgCC patients generally reacted slower than controls in a test of interhemispheric information integration, and showed reduced accuracy in trials that required interhemispheric integration. These findings indicate that reduced hemispheric specialization in the acallosal brain might be due to a higher degree of hemispheric autonomy in AgCC. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
    Neuropsychology 03/2015; DOI:10.1037/neu0000193 · 3.43 Impact Factor
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    ABSTRACT: Renewal in extinction learning describes the recovery of an extinguished response if the extinction context differs from the context present during acquisition and recall. Attention may have a role in contextual modulation of behavior and contribute to the renewal effect, while noradrenaline (NA) is involved in attentional processing. In this functional magnetic resonance imaging (fMRI) study we investigated the role of the noradrenergic system for behavioral and brain activation correlates of contextual extinction and renewal, with a particular focus upon hippocampus and ventromedial prefrontal cortex (PFC), which have crucial roles in processing of renewal. Healthy human volunteers received a single dose of the NA reuptake inhibitor atomoxetine prior to extinction learning. During extinction of previously acquired cue-outcome associations, cues were presented in a novel context (ABA) or in the acquisition context (AAA). In recall, all cues were again presented in the acquisition context. Atomoxetine participants (ATO) showed significantly faster extinction compared to placebo (PLAC). However, atomoxetine did not affect renewal. Hippocampal activation was higher in ATO during extinction and recall, as was ventromedial PFC activation, except for ABA recall. Moreover, ATO showed stronger recruitment of insula, anterior cingulate, and dorsolateral/orbitofrontal PFC. Across groups, cingulate, hippocampus and vmPFC activity during ABA extinction correlated with recall performance, suggesting high relevance of these regions for processing the renewal effect. In summary, the noradrenergic system appears to be involved in the modification of established associations during extinction learning and thus has a role in behavioral flexibility. The assignment of an association to a context and the subsequent decision on an adequate response, however, presumably operate largely independently of noradrenergic mechanisms.
    Frontiers in Behavioral Neuroscience 02/2015; 9:34. DOI:10.3389/fnbeh.2015.00034 · 4.16 Impact Factor
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    ABSTRACT: Because of their sophisticated vocal behaviour, their social nature, their high plasticity and their robustness, starlings have become an important model species that is widely used in studies of neuroethology of song production and perception. Since magnetic resonance imaging (MRI) represents an increasingly relevant tool for comparative neuroscience, a 3D MRI-based atlas of the starling brain becomes essential. Using multiple imaging protocols we delineated several sensory systems as well as the song control system. This starling brain atlas can easily be used to determine the stereotactic location of identified neural structures at any angle of the head. Additionally, the atlas is useful to find the optimal angle of sectioning for slice experiments, stereotactic injections and electrophysiological recordings. The starling brain atlas is freely available for the scientific community.
    Brain Structure and Function 02/2015; DOI:10.1007/s00429-015-1011-1 · 4.57 Impact Factor
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    ABSTRACT: The neural response to occasional variations of acoustic stimuli in a regular sequence of sounds generates an N-methyl-D-aspartate receptor-modulated event-related potential in primates and rodents in primary auditory cortex known as mismatch negativity (MMN). The current study investigated MMN in pigeons (Columba livia L) via intracranial recordings from Field L of the caudomedial nidopallium, the avian functional equivalent to the mammalian primary auditory cortex. Auditory evoked field potentials were recorded from awake birds by employing a low (800 Hz) and highfrequency (1400 Hz) deviant auditory oddball procedure with deviant-as-standard ("flipflop design") and multiple-standard control conditions. An MMN-like field potential was recorded and blocked with systemic 5 mg/kg ketamine administration. Our results are consistent with human and rodent findings of an MMN-like event-related potential in birds suggestive of similar auditory sensory memory mechanisms in birds and mammals that are homologue from a common ancestor 300 million years ago or resulted from convergent evolution.
    Neuroreport 02/2015; 26(5):239-244. DOI:10.1097/WNR.0000000000000323 · 1.64 Impact Factor
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    ABSTRACT: Prenatal androgen exposure has been suggested to be one of the factors influencing handedness, making the androgen receptor gene (AR) a likely candidate gene for individual differences in handedness. Here, we examined the relationship between the length of the CAG-repeat in AR and different handedness phenotypes in a sample of healthy adults of both sexes (n=1057). Since AR is located on the X chromosome, statistical analyses in women heterozygous for CAG-repeat lengths are complicated by X chromosome inactivation. We thus analyzed a sample of women that were homozygous for the CAG-repeat length (n=77). Mixed-handedness in men was significantly associated with longer CAG-repeat blocks and women homozygous for longer CAG-repeats showed a tendency for stronger left-handedness. These results suggest that handedness is associated with AR CAG-repeat length, with longer repeats being related to a higher incidence of non-right-handedness. Since longer CAG-repeat blocks have been linked to less efficient AR function, these results implicate that differences in AR signaling in the developing brain might be one of the factors that determine individual differences in brain lateralization.
    Scientific Reports 01/2015; 5. DOI:10.1038/srep08325 · 5.08 Impact Factor
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    ABSTRACT: Birds can rely on a variety of cues for orientation during migration and homing. Celestial rotation provides the key information for the development of a functioning star and/or sun compass. This celestial compass seems to be the primary reference for calibrating the other orientation systems including the magnetic compass. Thus, detection of the celestial rotational axis is crucial for bird orientation. Here, we use operant conditioning to demonstrate that homing pigeons can principally learn to detect a rotational centre in a rotating dot pattern and we examine their behavioural response strategies in a series of experiments. Initially, most pigeons applied a strategy based on local stimulus information such as movement characteristics of single dots. One pigeon seemed to immediately ignore eccentric stationary dots. After special training, all pigeons could shift their attention to more global cues, which implies that pigeons can learn the concept of a rotational axis. In our experiments, the ability to precisely locate the rotational centre was strongly dependent on the rotational velocity of the dot pattern and it crashed at velocities that were still much faster than natural celestial rotation. We therefore suggest that the axis of the very slow, natural, celestial rotation could be perceived by birds through the movement itself, but that a time-delayed pattern comparison should also be considered as a very likely alternative strategy.
    PLoS ONE 01/2015; 10(3):e0119919. DOI:10.1371/journal.pone.0119919 · 3.53 Impact Factor
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    Frontiers in Psychology 09/2014; 5. DOI:10.3389/fpsyg.2014.01143 · 2.80 Impact Factor
  • Onur Güntürkün, Maik C. Stüttgen, Martina Manns
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    ABSTRACT: Deeper understanding of the neuronal basis of behavior and its evolution requires investigation of model organisms taken from different taxonomic groups. The merits of this comparative approach are highlighted by research on birds: while their cognitive capacities have long been underestimated, research on avian model systems more recently has begun to provide central insights into the functional organization of the brain. In particular, domesticated homing pigeons (Columba livia) have been used as a model for the study of the psychological processes underlying learning, memory, and choice behavior, and much of current animal learning theory is based on findings with pigeons. Moreover, the vast amount of available behavioral and anatomical data has rendered the pigeon one of the key model species of behavioral and comparative neuroscience. This article illustrates some insights gained from research with pigeons with applicability beyond the class of aves.
    Neuroforum 09/2014; 5(4):86-92. DOI:10.1007/s13295-014-0057-5 · 0.04 Impact Factor
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    ABSTRACT: The avian hippocampal formation (HF) and mammalian hippocampus share a similar functional role in spatial cognition, but the underlying neuronal mechanisms enabling the functional similarity are incompletely understood. To better understand the organization of the avian HF and its transmitter receptors, we analyzed binding site densities for glutamatergic AMPA, NMDA and kainate receptors, GABAA receptors, muscarinic M1 , M2 and nicotinic (nACh) acetylcholine receptors, noradrenergic α1 and α2 receptors, serotonergic 5-HT1A receptors and dopaminergic D1/5 receptors using quantitative in vitro receptor autoradiography. Additionally, we performed a modified Timm staining procedure to label zinc. The regionally different receptor densities mapped well on to seven HF subdivisions previously described. Several differences in receptor expression highlighted distinct HF subdivisions. Notable examples include 1) high GABAA and α1 receptor expression, which rendered distinctive ventral subdivisions, 2) high α2 - receptor expression which rendered distinctive a dorsomedial subdivision, 3) distinct kainate, α2 and muscarinic receptor densities that rendered distinctive the two dorsolateral subdivisions, and 4) a dorsomedial region that was characterized by high kainate receptor density. We further observed similarities in receptor binding densities between subdivisions of the avian and mammalian HF. Despite the similarities, we propose that 300 hundred million years of independent evolution has led to a mosaic of similarities and differences in the organization of the avian HF and mammalian hippocampus, and that thinking about the avian HF in terms of the strict organization of the mammalian hippocampus is likely insufficient to understand the HF of birds. J. Comp. Neurol., 2014. © 2014 Wiley Periodicals, Inc.
    The Journal of Comparative Neurology 08/2014; 522(11). DOI:10.1002/cne.23549 · 3.51 Impact Factor
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    ABSTRACT: The metabotropic glutamate (mGlu) receptors and in particular, mGlu5, are crucially involved in multiple forms of forms of synaptic plasticity that are believed to underlie explicit memory. MGlu5 is also required for information transfer through neuronal oscillations and for spatial memory. Furthermore, mGlu5 is involved in extinction of implicit forms of learning. This places this receptor in a unique position with regard to information encoding. Here, we explored the role of this receptor in context–dependent extinction learning under constant, or changed, contextual conditions. Animals were trained over 3 days to take a left turn under 25% reward probability in a T-Maze with a distinct floor pattern (context A). On day 4, they experienced either a floor pattern change (context B) or the same floor pattern (context A) in the absence of reward. After acquisition of the task, the animals were returned to the maze once more on day 5 (context A, no reward). Treatment with the mGlu5 antagonist, MPEP, prior to maze exposure on day 4 completely inhibited extinction learning in the AAA paradigm but had no effect in the ABA paradigm. A subsequent return to the original context (A, on day 5) revealed successful extinction in the AAA paradigm, but impairment of extinction in the ABA paradigm. These data support that whereas extinction learning in a new context is unaffected by mGlu5 antagonism, extinction of the consolidated context is impaired. This suggests that mGlu5 is intrinsically involved in enabling learning that once-relevant information is no longer valid. © 2014 Wiley Periodicals, Inc.
    Hippocampus 08/2014; 25(2). DOI:10.1002/hipo.22359 · 4.30 Impact Factor
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    ABSTRACT: Sensory systems provide organisms with information on the current status of the environment, thus enabling adaptive behavior. The neural mechanisms by which sensory information is exploited for action selection are typically studied with mammalian subjects performing perceptual decision-making tasks, and most of what is known about these mechanisms at the single-neuron level is derived from cortical recordings in behaving monkeys. To explore the generality of neural mechanisms underlying perceptual decision making across species, we recorded single-neuron activity in the pigeon nidopallium caudolaterale (NCL), a non-laminated associative forebrain structure thought to be functionally equivalent to mammalian prefrontal cortex, while subjects performed a visual categorisation task. We found that, whereas the majority of NCL neurons unspecifically upregulated or downregulated activity during stimulus presentation, ~20% of neurons exhibited differential activity for the sample stimuli and predicted upcoming choices. Moreover, neural activity in these neurons was ramping up during stimulus presentation and remained elevated until a choice was initiated, a response pattern similar to that found in monkey prefrontal and parietal cortices in saccadic choice tasks. In addition, many NCL neurons coded for movement direction during choice execution and differentiated between choice outcomes (reward and punishment). Taken together, our results implicate the NCL in the selection and execution of operant responses, an interpretation resonating well with the results of previous lesion studies. The resemblance of the response patterns of NCL neurons to those observed in mammalian cortex suggests that, despite differing neural architectures, mechanisms for perceptual decision making are similar across classes of vertebrates.
    European Journal of Neuroscience 08/2014; 40(9). DOI:10.1111/ejn.12698 · 3.67 Impact Factor
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    Sarah Starosta, Maik C Stüttgen, Onur Güntürkün
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    ABSTRACT: While the subject of learning has attracted immense interest from both behavioral and neural scientists, only relatively few investigators have observed single-neuron activity while animals are acquiring an operantly conditioned response, or when that response is extinguished. But even in these cases, observation periods usually encompass only a single stage of learning, i.e. acquisition or extinction, but not both (exceptions include protocols employing reversal learning; see Bingman et al.(1) for an example). However, acquisition and extinction entail different learning mechanisms and are therefore expected to be accompanied by different types and/or loci of neural plasticity. Accordingly, we developed a behavioral paradigm which institutes three stages of learning in a single behavioral session and which is well suited for the simultaneous recording of single neurons' action potentials. Animals are trained on a single-interval forced choice task which requires mapping each of two possible choice responses to the presentation of different novel visual stimuli (acquisition). After having reached a predefined performance criterion, one of the two choice responses is no longer reinforced (extinction). Following a certain decrement in performance level, correct responses are reinforced again (reacquisition). By using a new set of stimuli in every session, animals can undergo the acquisition-extinction-reacquisition process repeatedly. Because all three stages of learning occur in a single behavioral session, the paradigm is ideal for the simultaneous observation of the spiking output of multiple single neurons. We use pigeons as model systems, but the task can easily be adapted to any other species capable of conditioned discrimination learning.
    Journal of Visualized Experiments 06/2014; 88. DOI:10.3791/51283
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    Emre Unver, Onur Güntürkün
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    ABSTRACT: In birds each hemisphere receives visual input from the contralateral eye. Since birds have no corpus callosum, avian brains are often seen as 'natural split brains'. How do birds cope with situations, when both hemispheres are brought into conflict? If under such conditions one hemisphere completely determines the response, this is called meta-control. This phenomenon has recently been demonstrated in pigeons. The aim of the current study is to test, if meta-control results from an interhemispheric conflict that would require interhemispheric interaction, possibly via the commissura anterior. To this end, we trained pigeons in a forced-choice color discrimination task under monocular condition such that each hemisphere was trained with a different pair of colors. Subsequently, pigeons were binocularly tested with conflicting and non-conflicting stimulus patterns. Conflicting stimuli indeed produced a delayed reaction time as expected when two divergent decisions create a conflict. In addition, we sometimes observed a pecking pattern that seemed to represent the average of two discrepant and hemisphere-specific movements. Thus, pigeons possibly undergo interhemispheric conflict during meta-control even without a corpus callosum. However, also when having decided to peck a certain color, the planned movement trajectory of the other hemisphere sometimes compromises the final pecking movement.
    Behavioural Brain Research 05/2014; 270. DOI:10.1016/j.bbr.2014.05.016 · 3.39 Impact Factor
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    ABSTRACT: Efforts to understand nervous system structure and function have received new impetus from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene-structure-function relationships that are not apparent from studies on single species. We here propose to extend the comparative approach to nervous system ‘maps’ comprising molecular, anatomical, and physiological data. This research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. These causal hypotheses can then be tested experimentally. Finally, insights from comparative research can inspire and guide technological development. To promote this research agenda, we recommend that teams of investigators coalesce around specific research questions and select a set of ‘reference species’ to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well-annotated genome, or other strategic reasons. We envision that the nervous systems of these reference species will be mapped in more detail than those of other species. The collected data may range from the molecular to the behavioral, depending on the research question. To integrate across levels of analysis and across species, standards for data collection, annotation, archiving, and distribution must be developed and respected. To that end, it will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be supported, at least in part, through existing mechanisms at NSF, NIH, and other agencies. It will also be important to develop new integrated software and database systems for cross-species data analyses. Multidisciplinary efforts to develop such analytical tools should be supported financially. Finally, training opportunities should be created to stimulate multidisciplinary, integrative research into brain structure, function, and evolution. J. Comp. Neurol., 2014. © 2014 Wiley Periodicals, Inc.
    The Journal of Comparative Neurology 05/2014; 522(7). DOI:10.1002/cne.23568 · 3.51 Impact Factor
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    ABSTRACT: Dominance of the left hemisphere for many aspects of speech production and perception is one of the best known examples of functional hemispheric asymmetries in the human brain. Classic theories about its ontogenesis assume that it is determined by the same ontogenetic factors as handedness because the two traits are correlated to some extent. However, the strength of this correlation depends on the measures used to assess the two traits, and the neurophysiological basis of language lateralization is different from that of handedness. Therefore, we argue that although the two traits show partial pleiotropy, there is also a substantial amount of independent ontogenetic influences for each of them. This view is supported by several recent genetic and neuroscientific studies that are reviewed in the present article.
    Neuroscience & Biobehavioral Reviews 04/2014; DOI:10.1016/j.neubiorev.2014.04.008 · 10.28 Impact Factor
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    ABSTRACT: Severe feather pecking (FP) is a detrimental behavior causing welfare problems in laying hens. Divergent genetic selection for FP in White Leghorns resulted in strong differences in FP incidences between lines. More recently, it was shown that the high FP (HFP) birds have increased locomotor activity as compared to hens of the low FP (LFP) line, but whether these lines differ in central serotonin (5-hydroxytryptamine, 5-HT) release is unknown. We compared baseline release levels of central 5-HT, and the metabolite 5-HIAA in the limbic and prefrontal subcomponents of the caudal nidopallium by in vivo microdialysis in adult HFP and LFP laying hens from the ninth generation of selection. A single subcutaneous d-fenfluramine injection (0.5mg/kg) was given to release neuronal serotonin in order to investigate presynaptic storage capacity. The present study shows that HFP hens had higher baseline levels of 5-HT in the caudal nidopallium as compared to LFP laying hens. Remarkably, no differences in plasma tryptophan levels (precursor of 5-HT) between the lines were observed. D-fenfluramine increased 5-HT levels in both lines similarly indirectly suggesting that presynaptic storage capacity was the same. The present study shows that HFP hens release more 5-HT under baseline conditions in the caudal nidopallium as compared to the LFP birds. This suggests that HFP hens are characterized by a higher tonic 5-HT release.
    Behavioural brain research 04/2014; 268. DOI:10.1016/j.bbr.2014.03.050 · 3.39 Impact Factor
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    ABSTRACT: Social communication through touch and mutual grooming can convey highly salient socio-emotional signals and has been shown to involve the neuropeptide oxytocin (OXT) in several species. Less is known about the modulatory influence of OXT on the neural and emotional responses to human interpersonal touch. The present randomized placebo (PLC)-controlled within-subject pharmaco-functional magnetic resonance imaging (fMRI) study was designed to test the hypothesis that a single intranasal dose of synthetic OXT (24 IU) would facilitate both neural and emotional responses to interpersonal touch in a context (female vs male touch) and trait (autistic trait load) specific manner. Specifically, the experimental rationale was to manipulate the reward value of interpersonal touch independent of the intensity and type of actual cutaneous stimulation administered. Thus forty heterosexual males believed they were touched by either a man or a woman, although in fact an identical pattern of touch was always given by the same female experimenter blind to condition type. Our results show that OXT increased the perceived pleasantness of female, but not male touch, and associated neural responses in the insula, precuneus, orbitofrontal and pregenual anterior cingulate cortex. Moreover, the behavioral and neural effects of OXT were negatively correlated with autistic-like traits. Taken together, this is the first study to show that the perceived hedonic value of human heterosexual interpersonal touch is facilitated by OXT in men, but that its behavioral and neural effects in this context are blunted in individuals with autistic traits.Neuropsychopharmacology accepted article peview online, 03 April 2014; doi:10.1038/npp.2014.78.
    Neuropsychopharmacology: official publication of the American College of Neuropsychopharmacology 04/2014; 39(9). DOI:10.1038/npp.2014.78 · 7.83 Impact Factor

Publication Stats

7k Citations
1,133.49 Total Impact Points

Institutions

  • 1985–2015
    • Ruhr-Universität Bochum
      • • Biopsychology
      • • Institut für Kognitive Neurowissenschaft (IKN)
      • • Faculty of Psychology
      Bochum, North Rhine-Westphalia, Germany
  • 2010
    • Heinrich-Heine-Universität Düsseldorf
      • C. u. O. Vogt-Institut für Hirnforschung
      Düsseldorf, North Rhine-Westphalia, Germany
  • 1993
    • Rutgers, The State University of New Jersey
      • Center for Molecular and Behavioral Neuroscience
      New Brunswick, NJ, United States
  • 1989–1993
    • Universität Konstanz
      • Faculty of Sciences
      Constance, Baden-Württemberg, Germany
  • 1992
    • University of Alaska Fairbanks
      • Institute of Arctic Biology
      Fairbanks, AK, United States